THEATER REVIEW; He May Think It's Passion, But She Knows It's Science

Last spring the Pulitzer Prize for drama went to a play about a mathematical proof. Last year New York imported a London stage hit about Heisenberg's uncertainty principle. So why not a play about intracytoplasmic sperm injection? But that drama, ''An Immaculate Misconception,'' doesn't come close to the depth of ''Proof'' or ''Copenhagen.'' It's a competent, straightforward but workmanlike play, written by Carl Djerassi, the Stanford University chemistry professor known as the father of the birth-control pill, now 77 and writing what he calls ''science in fiction.''

''An Immaculate Misconception'' begins with what looks like a one-night stand. Dr. Melanie Laidlaw (Ann Dowd), an American reproductive biologist, and Menachem Dvir (Thomas Schall), an Israeli nuclear engineer, have met at a scientific conference in Austria and, as she puts it, hopped into bed. Melanie is a widow in her late 30's who has no children. Menachem is a married man pushing 50 and has no children. As we soon find out, that's because of a radiation accident that left him virtually sterile.

What Menachem doesn't know is that Melanie is busy working on intracytoplasmic sperm injection -- ICSI (pronounced ICK-see), for short -- a new procedure in which, she hopes, fertilization can be achieved by injecting a single sperm into a single egg. And the next time she and Menachem meet, months later, she takes the unethical step of stealing and preserving his semen.

Back home at the lab Melanie has a partner, Dr. Felix Frankenthaler (David Adkins), who is not happy when he learns she's experimenting on her own eggs. He's even unhappier when he learns that the sperm in the experiment comes from a highly infertile man. Because Felix doesn't want to see this project fail, for the sake of his career, he has his own ethical lapse. When he acts on it, a complicated situation becomes even more complicated.

The cast, particularly Ms. Dowd and Mr. Schall, add much-needed warmth and humanity to the dialogue, which is a fairly cut-and-dried discussion of the procedure and the related playing-God issues (''All we'll be doing is improving the odds over nature's roll of the dice'') with the occasional stab at humor (''I don't want you to think I was a widow of opportunity''). In the real world, tens of thousands of babies have now been born as a result of ICSI; in 1999, an article in the journal Nature Medicine reported that the technique did alter the fertilization process and expressed concern about possible consequences.